Means for indicating the end of operation of a machine



.1. BOCHAN April 7, 1964 MEANS FOR INDICATING THE END OF OPERATION OF A MACHINE Filed Jan. 18, 1963 l 2 Sheets-Sheet 1 JOHN BOC HAN BY flay/ 4M Has ATTORNEV April 7, 1964 J, BOCHAN I 3,127,867

MEANS FOR INDICATING THE END OF OPERATION OF A MACHINE Filed Jan. 18, 1965 2 Sheets-Sheet 2 PIC-3.2

INVENTOR.

J'O HN BOCHAN BY wfime HIS ATTORNEY United States Patent 3,127,867 WANS FOR INDKEATING THE END OF OPERATIGN F A MACHINE John Boehan, Louisville, Ky, assignor to General Electric Company, a corporation of New York Filed Jan. 18, 1963, Ser. No. 252,338 Claims. (Cl. 11667) This invention relates to means for indicating the end of operation of a machine, and more particularly to structures which provide an audiable signal to indicate that the machine has ceased to operate.

It is an object of my invention to provide an end of cycle signal device which is automatically responsive to the termination of operation of a machine.

It is a further, more specific, object of my invention to provide such a device which does not require electrical actuation, but which utilizes centrifugal force to preclude provision of an audible signal during machine operation and to provide such a signal when the operation terminates.

In carrying out my invention in one form thereof, I provide a machine, such as a clothes dryer for instance, in which driving means provides operation of the machine, together with suitable control means for starting and terminating operation of the driving means. The driving means, which will generally be in the form of an electric motor, operates a shaft, and the nature of the machine is such that there is relatively rapid acceleration of the shaft when the driving means starts to operate and relatively rapid stopping of the shaft when operation of the driving means is terminated. A member which in cludes a striker is rotatably mounted on the shaft by low friction bearing means so that the member accelerates relatively slowly when the shaft starts to rotate and, by the same token, decelerates relatively slowly when the shaft stops.

Mounted to the shaft for rotation therewith is a movable assembly which includes a clapper and a counterweight. This assembly is biased by a spring to a first position wherein the clapper and the striker impact each other to produce an audible signal during relative rotation of the assembly and of the rotatably mounted member. It will be understood that such relative rotation occurs whenever operation is terminated since the shaft carrying the assembly rapidly comes to a stop Whereas the striker continues to rotate for a substantial period after the stopping of the shaft. During rotation of the shaft, the counterweight causes the assembly to move to a second position in response to centrifugal force. In this second position of the assembly, the clapper is in a position where it does not impact the striker during relative rotation of the assembly and the rotatably mounted member. Thus, in view of the fact that acceleration of the shaft is very rapid when operation starts, the clapper is moved almost instantly to a position Where it will not impact the striker, and it remains in that position until the operation stops at which time the audible signal is produced as described above.

The subject matter which I regard as my invention is particularly pointed out and distinctly claimed in the concluding portion of this specification. My invention, however, both as to organization and method of operation together with further objects and advantages thereof, may best be understood by reference to the following description taken in conjunction with the accompanying drawings.

In the drawings, FIGURE 1 is a side elevational view of a machine, more specifically a clothes dryer, which incorporates my improved end of cycle signal device, the view being partly broken away and partly sectionalized in order to illustrate details of the machine;

3,127,867 Patented Apr. 7, 1964 FIGURE 2 is an enlarged plan view of the improved end of cycle signal device of my invention, the view being partly broken away and partly in cross section in order to illustrate details; and

FIGURE 3 is a view along 3-3 in FIGURE 2.

Referring now to FIGURE 1, there is shown therein a typical machine in which my improved end of cycle signal device may be used, the particular machine illustrated being a domestic clothes dryer generally indicated by the numeral 1. Dryer 1 is provided in the usual way with a cabinet 2 having a front door 3 to provide access to the interior of the cabinet for loading and unloading clothes. Provided on the top wall 4 of the cabinet 2 is a control panel 5 which includes a suitable manual control 6 connected to a sequence control assembly 7. By manual presetting of control 6 the machine may be caused to start and automatically proceed through a cycle of operation, with control 7 causing the operation to be terminated after either a predetermined period or upon a predetermined occurrence, both such approaches being well known to those skilled in the art.

Within cabinet 2, there is provided a clothes tumbling container or drum 8 mounted for rotation on a substantially horizontal axis. Drum 8 is substantially cylindrical in shape, having a first cylindrical outer wall portion 9,

; second and third outer wall portions 10 and 11 located respectively adjacent the ends of the drum, a front wall 12 and a back wall 13. Outer wall portions 9, 10 and 11 are imperforate over their entire length so that the entire outer shell of the basket is imperforate. On the interior surface of central portion 14 there may be provided a plurality of clothes tumbling ribs 14 so that clothes are lifted up when drum 8 rotates and then tumble back down to the bottom of the basket.

The front of drum 8 may be rotatably supported within outer casing 2 by suitable idler wheels, one of which is shown by the numeral 15. These wheels are rotatably secured to the top of a member 16 which extends up from base 17 of the machine. Wheels 15 are disposed e eath the drum in contact with portion 10 thereof so as to support portion 19 on each side to provide a stable support.

The rear end of the drum 8 receives its support by means of a stub shaft 18 extending from the center of wall 13. Shaft 18 is secured within a bearing 19 formed in a baiile 20 which in turn is rigidly secured to the back Wall 21 of cabinet 2 by any suitable means such as, for instance, welding at a number of points 22. With the arrangement shown, the basket may rotate on a horizontal axis with rollers 15 providing the front support and the stub shaft 18 within bearing 19 providing the rear support.

In order to provide for the flow of a stream of drying air through the clothes drum, the drum is provided with a central aperture 23 in its front wall 12 and with an opening in the form of a plurality of perforations 24 in its rear wall 13, the perforations in the present case being formed to extend around the rear wall in an annulus.

As has been stated, bafile member 20 is rigidly secured to rear wall 21 of cabinet 2. Bafiie member 20 also serves to support heating means such as electric heating elements 25 appropriately insulated from the bafiie member. Heating elements 25 may be annular in shape so as to be generally coextensive with perforations 24 and drum 8. A baffie member 26 is rigidly secured to the back wall 13 of the drum outside the ring of perforations 24 and within the stationary baffle 2% so that an annular air inlet 27 is in efiect formed by bafiles 20 and 26. In this manner a passage is formed for air to enter annular inlet opening 27 between the bafiles, pass over the heating element 25, and then pass through openings 28 formed in bafile 26 to the interior of drum 8.

The front opening 23 of the drum is substantially closed by means of a stationary bulkhead generally indicated by the numeral 29. Bulkhead 29 is made up of a number of adjacent members including the inner surface 30 of access door 3, a stationary frame 31 for the door formed as a flange of the front wall 32 of the cabinet, the inner surface member 33 of an exhaust duct which is formed by the cooperation of member 33 with the front wall 32 of the cabinet, and an annular flange 34 mounted on frame 31 and on the duct wall. It will be noted that a suitable clearance is provided between the inner edge of the drum opening 23 and the edge of bulkhead 29 so that there is no rubbing between the drum and the bulkhead during rotation of the drum. In order to prevent any substantial air leakage through opening 23 between the interior and the exterior of the drum, a suitable ring seal 35, preferably formed of felt-like material, is secured to flange 34 in sealing relationship with the exterior surface of drum wall 12.

Front opening 23, in addition to serving as part of the air flow path through the drum, also serves as a means whereby clothes may be loaded into and unloaded from the drum. Door 3, whose inner surface forms part of the bulkhead closing the opening, is mounted on cabinet 2 so that when the door is opened clothes my be inserted into or removed from the drum through the door frame 31. It will be noted that the door includes an outer flat imperforate section 36 and an inwardly extending hollow section 3'7 mounted on the flat outer section. Hollow section 37 extends into the door frame 31 when the door is closed, and the door surface 30 which comprises part of the combination bulkhead 29 is actually the inner wall of the hollow section.

The air outlet from the drum is provided by a perforated opening 38 formed in the inner wall 30 of hollow door section 37. The bottom Wall section of door 3 and the adjacent wall of door frame 31 are provided with aligned openings 39 and 40, opening 40 providing the entrance to the duct 41 formed by the cooperation of member 33 with front wall 32. As shown, a lint trap 42, which may comprise a fine mesh bag, is preferably positioned in exhaust duct 41 at opening 40, the bag being supported by the door frame 31.

Duct 41 leads downwardly to an opening 43 formed in the member 16 which supports wheels 15. Opening 43 constitutes the inlet for a blower member 44 contained within a housing 45 and directly driven by an electric motor 46. Opening 43 provides the air inlet from duct 41 to blower 44 so that the blower may draw air in over the heaters 25 then through the basket and then through the door 3 and the duct 41 and into the blower. From the blower, the air passes through any appropriate duct (not shown) out of cabinet 2 so as to be exhausted from the machine.

In addition to driving blower 44, motor 46 has a shaft 47 with a small pulley 48 formed therein. A belt 49 extends around pulley 43 and also entirely around the cylindrical wall section 9 of drum 8; The relative circumferences of pulley 43 and wall section 9 cause the drum to be driven by the motor at a speed suitable to effect tumbling of fabrics therein. In order to provide proper tensioning of belt 49, there may be provided a suitable idler assembly 50 secured on the same support 51 which secures one end of the motor. Thus, the air is pulled through the drum and at the same time the fabrics in the drum are tumbled. When the air is heated by heating elements 25, the heated air passing through the drum causes vaporization of moisture from the clothes. The vapor is carried off with the air as it passes out of the machine.

It will be understood that when the manual control 6 is used to set the control assembly 7, it causes either continuous or intermittent operation of heater 25, and also starts the motor 46 so as to cause it to operate continuously until the end of an operation is tolled by the control '7. Preferably, the motor starting torque is suflicient to cause a rapid acceleration to substantially full speed. By the same token, the drag of drum 8 with the tumbling clothes therein, together with the effect of idler assembly 56 and blower 44, cause the shaft 47 to stop its rotation relatively quickly whenever the end of an operation is reached and control 7 causes the de-energization of motor 46.

Mounted on the end of shaft 47 is the improved end of cycle signal device 52 of my invention. Referring now to FIGURES 2 and 3 it will be seen that the end of shaft 47 is formed with a rectangular member 53, plane except for the center portion thereof which is formed as a hollow cylinder 54 having a cone-shaped base 55 for the hollow interior 56 thereof. A pivot member 57 is secured on one part 58 of member 53, and an assembly 59 is mounted on pivot 57 for pivotal movement thereon. Assembly 59 includes an arm 60 having a counterweight 61 formed at the end thereof. A spring 62, having one end secured on a pin 63 extending from part 64 of member 53 and the other end secured to the counterweight 61, biases assembly 59 to the position shown in solid outline in FIGURE 3 so that arm 60 rests against cylindrical part 54.

Assembly 5? includes a second arm 64a at the other end of which there is a pin 65 on which is pivotally mounted a clapper member 66. Member 66 is biased to the position shown by a spring 67 which has one end secured to counterweight 61 and the other secured to part 68 on the other side of pivot 65 from the clapper member.

When shaft 47 is stationary, or substantially stationary, assembly 59 is in the position shown, being biased to that position by spring 62. However, during the relatively high speed rotation of assembly 59 which occurs as a result of its being secured to rotate with motor shaft 47, centrifugal force acts on counterweight 61 and overcomes the bias of spring 62 to pivot assembly 59 to a second position, shown in broken outline in FIGURE 3. As can be seen, the radially outward movement of counterweight 61 from the center of rotation causes a corresponding inward movement of clapper 66. It will be understood that due to the rapid acceleration of motor 46, it is less than one full revolution before the speed is such as to cause assembly 59 to be moved to the position shown in broken outline. By the same token, because of the rapid stopping of shaft 47 at the end of an operation, the assembly 59 quickly moves back to the position shown in solid outline after an operation is terminated.

A U-shaped member 69 has the two ends 70 and 71 of its legs secured to parts 64 and 58 of member 53 so as to be movable therewith. Member 69 is provided with a central opening 72 in which there is fitted a spring member 73 preferably formed of hardened yet resilient steel. Member 73 has a small recess 74 formed at the center thereof in direct alignment with the bottom 55 of the hollow interior 56 of part 54.

A shaft 75 has its two ends 76 and '77 formed substantially conically so as to terminate in points which fit respectively in recess 74 and base 55. This forms a point hearing, of the same type actually as that used in jeweled bearings in watches, for instance. This type of bearing support provides low friction; as a result, rotation of shaft 47 will transmit only a small force to shaft 75 to cause it to rotate and therefore the acceleration of shaft '75 will be quite gradual. By the same token, when the shaft 47 stops rotation, the shaft 75 will continue to rotate after movement of shaft 47 has stopped, again because of the low friction.

Secured to shaft '75 so as to rotate therewith is a member 78 which terminates at its outer periphrey in an annular flange 79 positioned radially outward of clapper 66, as is most readily apparent in FIGURE 3. Secured to flange 79 at one point on the inner surface thereof is a striker member 8t? which, while it may take any desired shape, may for instance be in the form of a small solid cylinder as can be seen in the two FIGURES 2 and 3.

Striker 80 projects inwardly from flange 79 suliiciently so that, when clapper 66 is in the position shown in solid outline in FIGURE 3, the paths of rotation of striker 8t) and clapper 66 interfere. Consequently, if there is relative rotation of shaft 47 and member 78, striker 8t) and the clapper 66 will impact against each other. Each time this happens there will be an audible signal provided, the tonal qualities of the signal being, of course, dependent on the characteristics of the materials employed for the structure described. Upon each impact, the spring 67 permits clapper 66 to yield so that the striker 86, if it is rotating at high speed when clapper 66 is stopped, will, after striking clapper 66, proceed on its path and strike the clapper repeatedly, once for each rotation of striker 86.

When, however, assembly 59 is in the position shown in dotted outline, that is, when there is rotation of shaft 47, clapper 66 and striker 8%) are free to rotate relative to each other without striking.

Thus, at the beginning of an operation of dryer 1, when motor 46 starts to rotate, shaft 47 comes up to speed very rapidly causing clapper 66 to move from the position shown in solid outline to the position shown in dotted outline. This means either that there will be no impact at all between clapper 66 and striker $0, or else that there may be one impact before counterweight 61 causes the movement to the second position thereby to prevent any further impact.

As rotation of shaft 4'7 continues, the striker 80 slowly increases its rotational speed through the low friction bearing arrangement described. As a result, when the operation of machine 1 is terminated after an appropriate period, the shaft 47 rapidly comes to a stop but striker 80, being carried by shaft 75, is still rotating at high speed and is decelerating quite slowly because of the low friction bearings. Because rotation of shaft 47 has stopped, centrifugal force no longer acts on counterweight 61 to move assembly 59 to its second position, and it returns to the first position shown in solid outline in FIGURE 3. In this position, clapper 66 has now moved radially outward far enought so that it is struck by striker 80 once for each rotation thereof. Thus, there will be a series of bell-like sounds provided, thereby giving the operator a repeated audible signal indicating the termination of an operation.

It will be seen from the foregoing that my invention provides a simple structure which insures a substantial and audible signal which is repeated 2. number of times, the length of time the signal will be continued depending upon the exact design. In this connection, it will be understood that the smaller the mass of the structure mounted on shaft 75 (and thus the less the flywheel effect) the shorter will be the length of time that the signal is continued. It will further be observed that the signal is provided, without need for any electrical initiation thereof, by parts which are simple and reliable in operation.

While in accordance with the patent statutes I have described what at present is considered to be the preferred embodiment of my invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention and it is therefore aimed in the appended claims to cover all such equivalent variations as fall within the true spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. In a machine having driving means for providing operation of said machine, and control means for starting and terminating operation of said driving means:

(a) A shaft driven by said driving means, said machine being formed to effect relatively rapid acceleration of said shaft when operation of said driving means starts and relatively rapid stopping of said shaft when operation of said driving means is ter minated;

(b) a rotatably mounted member including a striker;

(c) low friction bearing means mounting said member on said shaft whereby said member accelerates relatively slowly upon rotation of said shaft and decelerates relatively slowly upon stopping of said shaft;

(d) a moveable assembly mounted to said shaft for rotation therewith, said assembly including a clapper and a counterweight;

(e) and biasing means biasing said assembly to a first position wherein said clapper and said striker impact each other to produce an audible signal during relative rotation of said assembly and said rotatably mounted member;

(f) said counterweight causing the assembly to move to a second position in response to centrifugal force during rotation of said assembly, said second position of said assembly moving said clapper to a position wherein it does not impact said striker during relative rotation of said assembly and said rotatably mounted member.

2. The structure defined in claim 1 wherein said assembly is mounted for pivotal movement between said first and second positions, said counterweight and said clapper being on opposite sides of the axis of rotation so that radial outward movement of said counterweight causes radially inward movement of said clapper.

3. The structure defined in claim 1 wherein said clappeer is positioned radially inward of said striker in said second position, and said second position is radially inward of said first position.

4. The structure defined in claim 1 wherein a second spring is provided connected to said clapper for resiliently mounting said clapper in position so that said clapper yields upon impact with said striker.

5. The structure defined in claim 1 wherein said rotatably mounted member includes a shaft having each end terminating in a conical shape, and said shaft includes means for receiving the points of the cones thereby to provide low friction bearings.

References Cited in the file of this patent UNITED STATES PATENTS 1,318,638 Anthon et al. Oct. 14, 1919 2,655,892 Manecke Oct. 20, 1953 3,031,768 Kurowski May 1, 1962 

1. IN A MACHINE HAVING DRIVING MEANS FOR PROVIDING OPERATION OF SAID MACHINE, AND CONTROL MEANS FOR STARTING AND TERMINATING OPERATION OF SAID DRIVING MEANS: (A) A SHAFT DRIVEN BY SAID DRIVING MEANS, SAID MACHINE BEING FORMED TO EFFECT RELATIVELY RAPID ACCELERATION OF SAID SHAFT WHEN OPERATION OF SAID DRIVING MEANS STARTS AND RELATIVELY RAPID STOPPING OF SAID SHAFT WHEN OPERATING OF SAID DRIVING MEANS IS TERMINATED; (B) A ROTATABLY MOUNTED MEMBER INCLUDING A STRIKER; (C) LOW FRICTION BEARING MEANS MOUNTING SAID MEMBER ON SAID SHAFT WHEREBY SAID MEMBER ACCELERATES RELATIVELY SLOWLY UPON ROTATION OF SAID SHAFT AND DECELERATES RELATIVELY SLOWLY UPON STOPPING OF SAID SHAFT; (D) A MOVEABLE ASSEMBLY MOUNTED TO SAID SHAFT FOR ROTATION THEREWITH SAID ASSEMBLY INCLUDING A CLAPPER AND A COUNTERWEIGHT; (E) AND BIASING MEANS BIASING SAID ASSEMBLY TO A FIRST POSITION WHEREIN SAID CLAPPER AND SAID STRIKER IMPACT EACH OTHER TO PRODUCE AN AUDIBLE SIGNAL DURING RELATIVE ROTATION OF SAID ASSEMBLY AND SAID ROTATABLY MOUNTED MEMBER; (F) SAID COUNTERWEIGHT CAUSING THE ASSEMBLY TO MOVE TO A SECOND POSITION IN RESPONSE TO CENTRIFUGAL FORCE DURING ROTATION OF SAID ASSEMBLY, SAID SECOND POSITION OF SAID ASSEMBLY MOVING SAID CLAPPER TO A POSITION WHEREIN IT DOES NOT IMPACT SAID STRIKER DURING RELATIVE ROTATION OF SAID ASSEMBLY AND SAID ROTATABLY MOUNTED MEMBER. 